Reference Guide

The following describes the priority group-bandwidth assignment.
Priority Group Bandwidth Assignment
IPC 5%
SAN 50%
LAN 45%
PFC and ETS Configuration Command Examples
The following examples show PFC and ETS configuration commands to manage your data center traffic.
Example of Configuring QoS Priority-Queue Assignment to Honor Dot1p Priorities
Dell(conf)# service-class dynamic dot1p
Or
Dell(conf)# interface tengigabitethernet 1/1
Dell(conf-if-te-1/1)# service-class dynamic dot1p
Example of configuring a DCB Map
dcb-map test
priority-group 1 bandwidth 50 pfc on
priority-group 2 bandwidth 45 pfc off
priority group 3 bandwidth 5 pfc off
priority-pgid 2 2 2 1 3 2 2 2
Example of Applying DCB Map to an Interface
Dell(conf)# int tengigabitethernet 1/1
Dell(conf-if-te-1/1)# dcb-map test
Using PFC and ETS to Manage Converged Ethernet Traffic
Using PFC and ETS to manage converged ethernet traffic:
dcb-map linecard all backplane all dcb-map-name
Hierarchical Scheduling in ETS Output Policies
ETS supports up to three levels of hierarchical scheduling.
For example, you can apply ETS output policies with the following configurations:
Priority group 1
Assigns traffic to one priority queue with 20% of the link bandwidth and strict-priority scheduling.
Priority group 2 Assigns traffic to one priority queue with 30% of the link bandwidth.
Priority group 3 Assigns traffic to two priority queues with 50% of the link bandwidth and strict-priority scheduling.
In this example, the configured ETS bandwidth allocation and scheduler behavior is as follows:
Unused
bandwidth usage:
Normally, if there is no traffic or unused bandwidth for a priority group, the bandwidth allocated to the
group is distributed to the other priority groups according to the bandwidth percentage allocated to each
group. However, when three priority groups with different bandwidth allocations are used on an interface:
● If priority group 3 has free bandwidth, it is distributed as follows: 20% of the free bandwidth to
priority group 1 and 30% of the free bandwidth to priority group 2.
Data Center Bridging (DCB) 237